Field of the Invention
The present disclosure relates to a liquid ejection head and a liquid ejection apparatus, and, more particularly, relates to a technique that reduces an effect of a cavitation on a heating element in a liquid ejection head that ejects liquid, such as ink.
Description of the Related Art
A method that ejects ink using a heating element is a method in which a bubble is formed in the liquid with the heat generated by the heating element and the liquid is ejected from an ejection port with the pressure of the bubble. In such a method, when the bubble that has been formed on the heating element disappears, a cavitation is formed. The cavitation may have an adverse effect, such as shortening the life of the heating element.
Conversely, Japanese Patent Laid-Open No. 2012-179902 discloses a liquid ejection head in which a center of an ejection port is offset with respect to a center of a heating element in a direction in which the ink is supplied to the heating element. Such a liquid ejection head is capable of performing atmospheric communication without dividing the bubble while the bubble is disappearing. With the above, formation of a cavitation on the heating element with the divided bubble can be suppressed, and the adverse effect on the life of the heating elements can be reduced.
However, the ejection configuration of the print head disclosed in Japanese Patent Laid-Open No. 2012-179902 is for a type of print head in which atmospheric communication is performed while the bubble is disappearing. Accordingly, in a type of print heads that do not perform atmospheric communication, the mechanism of suppressing the cavitation is different and the technique disclosed in Japanese Patent Laid-Open No. 2012-179902 cannot be used as it is.